Roll With a Means for Holding Windings

ABSTRACT

The invention relates to a roll including a sheet (F) made of a flexible material, such as an absorbent fibrous material, formed by winding the sheet around a winding axis while creating a hole in the center and that presents a first set ( 10 ) of windings bonded to each other. The roll is characterized by the fact that it includes a second set ( 20 ) of windings that are not bonded to each other, between the center hole and the first set ( 10 ). The roll, according to the invention, holds up well throughout its use and is easily placed into service, in particular in the case of a roll of the center pull type.

The invention relates to the field of products made of absorbent paper,tissue paper, or other similar material such as a nonwoven, the productsbeing presented as rolls and intended for drying. The invention relatesin particular to the field of products for sanitary or household use,such as rolls of paper for drying, hand towel rolls, or toilet paperrolls.

For these applications, the rolls are made up of a continuous sheet thatincludes one or several plies. The sheet is optionally pre-cut intosuccessive sections in the winding direction, and is rolled up axially,preferably around a support, a spindle for example, that may or may notsupport a core; thus the roll may or may not include a central core.

The sheet of the outer winding can be unwound from the periphery of theroll, in the winding direction. In this case, it is said that this is aroll for tangential unwinding. After having, if applicable, removed thecore, the sheet of the inner winding can be unwound through the inside,from the center, in the axial direction, perpendicular to the windingdirection of the roll. In the latter case, the roll is a center pulltype roll.

As regards coreless rolls, the collapsing of the walls of the centralhole can create a problem. Indeed, due to the more or less strong pullexerted on the sheet during rolling up and due to the elasticity of thesheet, a tightening occurs which tends to ease up in the central areaupon extraction of the roll from the support that was used for winding.This collapsing can also occur in the event of saw cutting or duringroll handling. This is also known to happen with rolls from which thecore was previously extracted.

This makes the product particularly difficult to use in the case ofcenter pull rolls, because after the collapsing, little room remains forgrabbing the first sheet. The user is thus led to grab several sheets,which is a source of waste. In the case of a roll for tangentialunwinding, the lack of a central hole makes it difficult to mount onto asupporting axis of a dispenser.

In the case of a coreless center pull product, a solution was proposedby the applicant in patent applications WO2005/005295 and FR04 05022.The solution includes forming a leader for grabbing purposes bylaterally moving the free end of the sheet, in such a way that it jutsout of one of the sides of the roll.

However, this solution can prove inefficient if the roll was definedwith poor precuts and if the central hole is deformed or, even worse,fully collapsed. Indeed, the first pre-cut sheet can then becomedetached during extraction of the leader, with the next sheets thenbecoming difficult, if not impossible, to access.

In addition, during utilization of the roll for center pulling in asuitable dispenser, and if the walls of the roll are not held in place,the walls can collapse at any time and result in the forming of ajamming around the dispensing aperture, thus preventing its continuoususe.

Other solutions relate to the use of a bonding agent, water, additive,glue, or any other material, so as to maintain the hole formed afterextraction of the reel from its winding support, until it is used.However, these solutions are not entirely satisfactory either.

A bonding agent applied onto the first windings of a reel makes itpossible to create a well-formed hole, whose aspect is dependent on theprofile of the spindle. For example, spindles with a polygonal, grooved,or cylindrical section are used. These spindles lead to the forming of ahole with a corresponding profile. However, as these first windings areconnected to each other, it is not possible to extract the first sheetalone. It is often impossible to avoid pulling them off all at oncewhich inevitably generates waste. Furthermore, beyond these firstconnected windings, the walls are no longer held in place; thus they cancollapse during use or at any other time.

The depositing of a bonding agent onto the first windings, but only inthe median area of the sheet, while leaving the edges free of glue, hasbeen considered. The grabbing of the first sheet is thus facilitated,but the problem of collapsing is not fully resolved, in particularduring its use.

As taught by U.S. Pat. No. 6,179,235, a bonding agent can be appliedonto at least one of the two vertical sides of a roll, or onto at leastone of the edges of a sheet. However, these means can not efficientlyavoid collapsing during dispensing, in particular for large sizeproducts.

The invention proposes a solution that avoids the disadvantages of theprevious solutions.

According to the invention, a coreless roll, comprising a flexiblematerial sheet, such as an absorbent fibrous material, formed by windingof the sheet around a winding axis that creates a hole in the center andthat presents a first set of windings bonded to each other, ischaracterized by the fact that it includes a second set of non bondedwindings, between the center hole and the first set.

One winding corresponds to one rotation inside the roll. The bondedwindings are windings that are connected to each other by any bondingmeans, including water, but whose separation from one another remainseasily accomplished under normal usage conditions for the unwinding.

The solution under the invention has the advantage that it can beimplemented very simply, by placing the bonding means, for examplespraying a liquid substance, in an appropriate manner during winding ofthe sheet. No additional arrangement needs to be provided. Preferably,the liquid substance is water or an aqueous adhesive substance.

Advantageously, the number of non bonded windings of the second set ishigher than or equal to two. It is preferably less than the number ofwindings corresponding to 10% of the roll length.

The solution under the invention applies in particular to rolls of thetight winding type, which permit the manufacture of dense rolls calledcompact rolls. Such rolls can be manufactured for use under center pullconditions, preferably with one free end of the first winding from thecentral hole, exceeding the side of the roll, or for use undertangential unwinding conditions.

According to another characteristic of the invention, the roll comprisesat least one additional set of windings bonded to each other, betweenthe first set of bonded windings and the periphery of the roll, thesesets of bonded windings being separated from each other by non bondedwindings. This succession of non bonded windings and sets of bondedwindings can be repeated at will based on needs, and depending on thenon-collapsibility of the winded material and on the greater or smallersize of the reel. This solution also presents the advantage of avoidingthe collapse of the walls when a large part of the roll has already beenused up and when the hole has become sizeable.

The bonding agent application can vary between each roll and betweeneach bonded winding of the same roll, both as to the nature of thebonding agent, the area covered, the quantity, the length and as to theposition of the bonding agent.

An object of the invention is also a roll manufacturing process, whereina sheet is winded around a winding axis, and a bonding agent is appliedso as to bond windings to each other, after forming a specific number ofwindings that are not bonded to each other. The non bonded windings arethe first windings formed upon winding around the winding axis.

The invention shall be better understood, and additional advantagesshall appear, upon reading the following description. The descriptiondetails an embodiment with reference to the attached drawings, wherein:

FIG. 1 represents, in diagram form, a paper roll as claimed by theinvention,

FIGS. 2 to 4 show a manufacturing process for rolls based on a parentroll,

FIG. 5 shows a means for forming a center pulling leader.

FIG. 1 shows a roll 1 lying on one of the lateral sides forming one ofits “flanks.” For example, this can be a drying paper roll for centerpulling, from which the core, if any, was removed. Sheet F is rolled upcontinuously starting at the center. The FIGURE represents the inner endof the roll with the first sheet F1 partially extracted. In the absenceof a means for holding the windings at the axis, the central hole willhave a natural tendency to close. It then becomes difficult to grab theend of the first sheet alone. It is already known in the prior art thatthe sheets can be glued to each other near the first windings. However,while the windings that form the periphery of the central hole areconsolidated, there remains, in this interconnected area, the difficultyof individually grabbing the sheet constituting the first winding.

According to the invention, the risk of collapse is reduced by forming abonded area, but by leaving the sheets of the very first windingsbonding-free, so that the user will find it easy to start off the reel.The bonded area is defined so as to guarantee a sufficient cohesivenessbetween the windings to ensure that the roll holds up well whilepermitting an easy separation of these windings under normal unwindingconditions. In the example of FIG. 1, an initial set 10 is shown inthick lines where the windings are bonded to each other.

Between the central hole and this first set 10, there are non bondedwindings. These form a second set 20.

Thanks to this particularly simple solution, the walls of the centralhole are reinforced by bonding a number of windings to each other,however, the first sheet(s) constituting at least the first two windingsremain(s) free and can thus be grabbed without any difficulty.

In the extreme, only the first two windings are unconnected; all otherwindings of the roll are bonded to each other, thus forming a single setof bonded windings.

According to another possibility, in order to lower the risks of seeingthe central hole close up, the walls of the reel are consolidated withat least one, or preferably several, additional and noncontiguous set(s)(11, 12) of bonded windings; their number essentially depends on thedimensions of the roll. The sets of noncontiguous bonded windings (10,11, 12) are separated from each other by non bonded windings (21, 22).

In particular, the one or several set(s) of bonded windings comprise anumber of windings ranging from 4 to 20.

Even more particularly, for a drying product with a diameter of 20 cm,the first 20 windings will be kept free and a single first set of 15bonded windings will be necessary.

A manufacturing process of the discontinued type, commonly called “stop& go” by the expert is described, in connection with FIGS. 2, 3, and 4.

FIG. 2 shows the diagram of a manufacturing process for rolls. A parentroll 103, made of tissue paper for example, is unwound at its support.Sheet F is driven toward the roll forming station. The parent roll 103has a width of 2.60 m for example. The sheet is cut longitudinally inrelation to its running direction by means of knife blades 105. Thus, asheet with a width of 2.60 m can be cut into 13 strips 100 that are 20cm wide. The strips 100 are guided to make them come to a set of twocylinders 107 and 109 that are laid out side by side. Once thedownstream ends 100A have passed cylinder 109, a spindle 111, that mayor may not be outfitted with cores, is placed onto strips 100, near thehollow created between the two cylinders 107 and 109, upstream of thedownstream ends 100A. A means 115 displaces the ends 100A of strips 100above the spindle 111 that may or may not be outfitted with a core.Preferably, this means comprises air jets that are suitably directed. Itcan be seen from FIG. 3 that the end is in the process of being flippedback. Next there is lowered a supporting cylinder 113, whose function isto hold the ends 100A onto the spindle 111 that may or may not beoutfitted with cores, as well as spindle 111 that may or may not beoutfitted with cores onto the two cylinders 107 and 109, and to compressthe sheet during winding. The rotary drive of at least one of cylinders107, 109 or 113 is commanded; this drives spindle 111 as well as strips100. Rewinding starts and rolls 110′ are formed.

In accordance with the invention, we placed on the path of strips 100 abonding agent applying means 118 for connecting the windings to eachother. This bonding agent can be water, but an adhesive substance canalso be used. This means is for example placed upstream from cylinders107 and 109, and applies the bonding agent on the surface of sheets 100.In the case of a liquid agent, the applying means is preferably asprayer. The surface of the sheet that receives the sprayed liquid, theamount applied, the continuous or discontinuous application mode, inparticular, are determined according to need. Due to the pressureexerted onto the sheet during winding, water for example permits, in theareas of contact of the windings between each other, the forming ofbonds between the tissue fibers. These bonds permit the connecting ofthe windings. However, this connection is accomplished in such a way asto ensure an easy separation of the bonded windings during normalunwinding operation either through the center or tangentially.

The applying of the bonding agent may or may not be interrupted untilthe rolls are formed.

According to another characteristic of the invention, the applying ofthe bonding agent is temporarily interrupted and subsequently resumed soas to form another set of bonded windings, separated from the first oneby a set of non bonded windings. This succession of non bonded andbonded windings may be repeated at will. It is understood that theselection of the number of bonded winding sets depends on the targetedobjective, on their frequencies, and on the dimensions of the roll. Awide roll with a large diameter shall incorporate several areas toaccommodate the unwinding and to prevent the walls from collapsing whenin use or at any other time.

According to another characteristic of the invention, the bonding agentapplication varies between each roll or between each bonded winding ofthe same roll, according to at least one of the following parameters:nature of the bonding agent deposited, its quantity, its position inrelation to the sheet, the surface, or the shape covered.

Upon reaching the desired diameter, the spindle-and-rolls set is takenaway. The plurality of strips 100 is cut by means of a transversalknife. After winding of the end of strips 100, the rolls are extracted.In the case of a coreless roll, this operation will be facilitated bythe use of a conical spindle or, as is known from the prior art, by theuse of a mechanized spindle with an adjustable diameter. In order topermit an easier extraction, these spindles may or may not be coatedwith a coating that reduces their coefficient of friction.

According to another manufacturing process, a cylinder without anylongitudinal cutting 105 is formed upstream from the winding. Uponextraction of the winding support, this cylinder is sawn off intoindividual rolls.

According to another characteristic of the invention, the techniquedetailed in the two patent applications filed on behalf of thisapplicant WO2005/005295 and FR04 05022 is applied. According to thistechnique, the objective is to create a leader for grabbing purposes bydisplacing, laterally in relation to the running direction, the end ofsheet 110A constituting the first winding. This portion then juts outfrom the roll and ensures that the sheet will be extracted without anyproblem.

Another process for forming a leader for unwinding purposes isrepresented on FIG. 5. A cylinder 200 with a diameter less than that ofthe central hole has perforations 210. It is connected to a vacuumsource not shown in the FIGURE. After having formed the rolls accordingto the invention and after having removed the core, if any, cylinder 200is introduced into the central hole and the inside of the cylinder isplaced in the suction mode. As the first winding is free, it is drawnagainst cylinder 200 due to the suction. Cylinder 200 is then rotated bya fraction of a rotation on itself in a predetermined direction, it isthen extracted from the roll. The sheet is then driven by the movement.When the extracted sheet exceeds the desired length from the side of theroll, the vacuum is cut and the cylinder is taken away. The roll is thusready for use.

1-13. (canceled)
 14. A roll comprising a sheet of flexible materialwound around a winding axis with a hole in a center of the roll andincluding a first set of windings bonded to each other and a second setof windings not bonded to each other wherein the second set ispositioned between the center hole and the first set.
 15. The rollaccording to claim 14, wherein the flexible material is an absorbentfibrous material.
 16. The roll according to claim 15, wherein the secondset comprises windings in a number greater than or equal to
 2. 17. Theroll according to claim 14, wherein the first set comprises windings ina number greater than or equal to
 2. 18. The roll according to claim 14,further comprising a plurality of the second set which are noncontiguousand separated from each other by non bonded windings.
 19. The rollaccording to claim 14, wherein the first set incorporates a bondingagent.
 20. The roll according to claim 19, wherein the bonding agent asapplied to a winding of the roll can vary in application according to atleast one parameter including nature of the bonding agent, quantity ofthe bonding agent, position of the bonding agent, or surface or shapecovered by the bonding agent.
 21. The roll according to claim 19,wherein the bonding agent is a liquid substance.
 22. The roll accordingto claim 21, wherein the liquid substance is chosen from the groupconsisting of water or an aqueous adhesive.
 23. The roll according toclaim 14, wherein the roll further comprises tight winding to define adense roll.
 24. The roll according to claim 14, wherein the roll allowsunwinding of the sheet through the center of the roll.
 25. The rollaccording to claim 24, wherein a free end of a first winding from thehole in the center extends from the side of the roll.
 26. The rollaccording to claim 14, wherein the windings in the first set are bondedtogether by a bonding means permitting separation of one winding fromanother upon unwinding.
 27. The roll according to claim 26, wherein thebonding means comprises water.
 28. The roll according to claim 26,wherein the bonding means comprises an aqueous adhesive substance. 29.The roll according to claim 14, wherein the roll allows unwinding of thesheet tangentially from the roll.
 30. The roll according to claim 14,wherein the windings in the first set are bonded together by a bondingmeans permitting separation of one winding from another upon unwinding.31. The roll according to claim 30, wherein the bonding means compriseswater.
 32. The roll according to claim 30, wherein the bonding meanscomprises a watery adhesive substance.
 33. The process of manufacturinga roll according to claim 14, comprising the steps of winding the sheetaround a winding axis and applying a bonding agent to bond the windingsof the first set to each other, and thereafter forming a predeterminednumber of windings of the second set.
 34. The process of manufacturing aroll according to claim 33, wherein the flexible material is anabsorbent fibrous material.
 35. The process according to claim 34,wherein the step of applying of the bonding agent comprises projecting aliquid substance onto the sheet.
 36. The process according to claim 34,wherein the roll allows unwinding of the sheet through the center of theroll.
 37. The process according to claim 36, comprising the step ofwithdrawing a free end of a first winding from the hole in the centerand positioning it so that it extends from the side of the roll.
 38. Theprocess according to claim 37, wherein the free end of the first windingis withdrawn from the hole in the center and positioned it so that itextends from the side of the roll by means of a perforate tube to whichvacuum is applied.
 39. The process according to claim 35, wherein aplurality of the second set are noncontiguous and separated from eachother by non-bonded windings.
 40. The process of manufacturing a rollaccording to claim 35, where the second set comprises windings in anumber greater than or equal to
 2. 41. The process of manufacturing aroll according to claim 14, comprising winding the sheet around awinding axis and applying a bonding agent to non-permanently bond thewindings of the first set to each other, and forming a predeterminednumber of windings of the second set.
 42. The process according to claim41, wherein the step of applying of the bonding agent comprisesprojecting a liquid substance onto the sheet.
 43. The process ofmanufacturing a roll according to claim 42, wherein the flexiblematerial is an absorbent fibrous material.
 44. The process according toclaim 43, wherein the roll allows unwinding of the sheet through thecenter of the roll.
 45. The process according to claim 44, comprisingthe step of withdrawing a free end of a first winding from the hole inthe center and positioning it so that it extends from the side of theroll.
 46. The process according to claim 45, wherein the free end of thefirst winding is withdrawn from the hole in the center and positioned itso that it extends from the side of the roll by means of a perforatetube to which vacuum is applied.
 47. The process according to claim 46,wherein a plurality of the second set are noncontiguous and separatedfrom each other by non-bonded windings.